Pictures of a duplicate of the Honda NC35 HRC airbox lid. I believe this aribox lid was made by Pete Panagi of the NC30 Club, possibly purchased through RLR Motorsports. Shown in the pictures are the HRC airbox lid on the left, and a stock NC35 airbox lid on the right.

The HRC airbox lid is all that is required to make an NC35 HRC airbox. You remove the stock airbox lid, remove the air filter element and screw this HRC lid in their place. You also have to modify a couple hoses and fit them to the white knee joint shown in the pictures below (see the NC35 HRC manual). Note that the NC35 HRC airbox does not use an air filter. This airbox lid is designed to work with the Honda NC35 HRC carb kit. A copy of the Honda HRC manual, and an english translation can be found here.

(click on image for a larger version)